@FL: {  // flexLayout
    display: flex;
    justify-content: center;
    align-items: center;
}
@w: {  // public_element
    max-width: 1234px;
    margin: 0 auto;
    padding: 0 30px;
}
// header
.topbar {
    height: 42px;
    line-height: 42px;
    background-color: #000;
    color: #fff;
    font-size: 15px;
    text-align: center;
}
// background盒子
.bg {
    width: 100%;
    height: 1200px;
    background: linear-gradient(189.16deg, rgb(57, 15, 199) 13.57%, rgb(40, 35, 77) 98.38%);
    overflow: hidden;
    position: absolute;
    z-index: -1;
    & .ball1 {
        width: 500px;
        height: 500px;
        background-color: pink;
        position: absolute;
        top: 250px;
        left: 200px;
        background: linear-gradient(rgba(186, 117, 255, 0.49) 26.56%, rgb(57, 19, 184) 100%);
        animation: move 30s infinite alternate;
    }
    & .ball2 {
        width: 500px;
        height: 500px;
        background-color: pink;
        position: absolute;
        top: 250px;
        left: 200px;
        background: linear-gradient(rgba(47, 184, 255, 0.42) 31.77%, rgb(158, 236, 217) 100%);
        animation: move 25s infinite alternate;
    }
}
@keyframes move {
    0% {
        transform: translate(-200px, 0px) rotate(-90deg);
        border-radius: 51% 49% 58% 42% / 34% 78% 22% 66%;
    }
    100% {
        transform: translate(400px, 100px) rotate(-120deg);
        border-radius: 22% 78% 73% 27% / 67% 31% 69% 33%;
    }
}
.header {
    @w();
    display: flex;
    justify-content: space-between;
    padding-top: 60px;
    & .logo img {
        width: 44px;
        height: 44px;
        margin: 0;
    }
}
.nav {
    display: grid;  // 为responsive做铺垫
    grid-template-columns: repeat(7, auto);  // auto根据内容来走
    gap: 26px;
    & a button {
        display: flex;
        padding: 10px 20px;
        background: none;
        border: 0;
        border-radius: 14px;
        cursor: pointer;
        transition: 0.3s ease-in-out;
    }
    & a button:hover {
        background: #ffffff33;
        box-shadow: #1f2f4740 0px 20px 40px, #0000001a 0px 1px 5px, #ffffff66 0px 0px 0px 0.5px inset;
    }
    & a button img {
        width: 24px;
        height: 24px;
    }
    & a button p {
        font-size: 15px;
        color: #fff;
        margin-left: 10px;
    }
}
.mobile-nav {  //hiddenBox
    @FL();
    display: none;
    width: 44px;
    height: 44px;
    background: rgba(15, 14, 71, 0.3);
    box-shadow: rgba(255, 255, 255, 0.2) 0px 0px 0px 0.5px inset;
    backdrop-filter: blur(40px);
    border-radius: 50%;
}
// responsive_navigationBar
@media screen {
    @media (max-width: 1024px) {
        .nav {
            grid-template-columns: repeat(6 ,auto);
        }
        .nav a:nth-child(4) {
            display: none;
        }
    }
    @media (max-width: 900px) {
        .nav {
            grid-template-columns: repeat(5, auto);
        }
        .nav a:nth-child(3) {
            display: none;
        }
    }
    @media (max-width: 768px) {
        .nav {
            grid-template-columns: repeat(4, auto);
        }   
        .nav a:nth-child(2) {
            display: none;
        }
    }
    @media (max-width: 550px) {
        .nav {
            display: none;
        }
        .header {
            padding-top: 20px;
        }
        .mobile-nav {
            display: flex;
        }
    }
}
// courseBox
.course {
    @w();
    display: grid;
    grid-template-columns: 380px auto;
    align-items: end;
    gap: 80px;
    margin-top: 60px;
}
.course-l {
    color: #fff;
    & .time {
        font-size: 15px;
        font-weight: 600;
        line-height: 18px;
        color: rgba(255, 255, 255, 0.7);
    }
    & h2 {
        font-size: 40px;
        line-height: 48px;
        margin: 20px 0;
    }
    & p {
        font-size: 17px;
        line-height: 24px;
        color: rgba(255, 255, 255, 0.7);
    }
}
.course-r {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
}
.icon ul {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 20px;
    & li {
        list-style: none;
        img {
            width: 44px;
            height: 44px;
        }
    }
}
.search {
    position: relative;
}
.search input {
    border: 0;
    outline: 0;
    width: 204px;
    height: 44px;
    padding: 10px 42px;
    border-radius: 30px;
    background: linear-gradient(rgba(99, 106, 150, 0.8) 0%, rgba(182, 186, 214, 0.6) 100%);
    box-shadow: rgba(0, 0, 0, 0.15) 0px 20px 40px, rgba(255, 255, 255, 0.3) 0px 0px 0px 0.5px inset;
    color: #fff;
}
.search img {
    position: absolute;
    left: 10px;
    top: 10px;
    width: 24px;
    height: 24px;
}
.search input:focus {
    box-shadow: rgba(47, 184, 255, 0.3) 0px 10px 40px, rgb(47, 184, 255) 0px 0px 0px 1px inset;
    background: linear-gradient(rgba(24, 32, 79, 0.4) 0%, rgba(24, 32, 79, 0.25) 100%);
}
// course_@media
@media screen {
    @media (max-width: 1280px) {
        .course {
            grid-template-columns: 1fr;
        }
        .course-l {
            max-width: 380px;
        }
    }
    @media (max-width: 1024px) {
        .course-l {
            max-width: 380px;
            margin: auto;
            text-align: center;
        }
    }
    @media (max-width: 700px) {
        .course-r {
            display: grid;
            gap: 20px;
            // 注意区分
            justify-content: center;
            justify-items: center;
        }
    }
}
// course_card
.course-card {
    display: grid;
    // 核心代码
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 40px;
    max-width: 1254px;
    margin: 40px auto 0px;
    padding: 0px 40px;
    & .item {
        height: 360px;
        background: pink;
        border-radius: 20px;
        padding: 20px;
        background: linear-gradient(209.21deg, #494ffe 13.57%, #0f1324 98.38%);
        cursor: pointer;
        transition: 0.8s cubic-bezier(0.075, 0.82, 0.165, 1);
        & figure {
            position: relative;
            height: 150px;
            text-align: center;
            & > img {
                width: 200px;
                height: 150px;
                object-fit: cover;
                transition: 0.8s cubic-bezier(0.075, 0.82, 0.165, 1);
            }
        }
        & h3 {
            color: #fff;
            font-size: 24px;
            line-height: 140%;
            text-align: center;
            font-weight: 600;
            margin: 10px 0;
            height: 100px;
            // 多行显示省略号
            overflow: hidden;
            text-overflow: ellipsis;
            display: -webkit-box;
            -webkit-line-clamp-: 3;
            -webkit-box-orient: vertical;
        }
        & p {
            font-size: 15px;
            color: rgba(255, 255, 255, 0.7);
            text-align: center;
        }
    }
    & .item:hover {
        transform: scale(1.1);
        box-shadow: #0f13244d 0px 20px 40px, #0000000d 0px 1px 3px;
        & figure > img {
            transform: scale(0.9);
        }
    }
    & .star {
        width: 32px;
        height: 32px;
        margin: 0 auto;
        background-color: rgba(0, 0, 0, 0.2);
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        margin-top: 10px;
    }
    & .item4 {
        background: linear-gradient(209.21deg, #f28885 13.57%, #e94f66 98.38%);
    }
}
// 避免“嵌套地狱”，工程上仅嵌套三四层最多
.course-card .item figure .icon1,
.course-card .item figure .icon2 {
    width: 32px;
    height: 32px;
    position: absolute;
    right: 0;
    border-radius: 50%;
    overflow: hidden;
}
.course-card .item figure .icon1 {
    top: 0 !important;
}
.course-card .item figure .icon2 {
    top: 42px !important;
}
// course_card_responsive
@media (max-width: 768px) {
    .course-card {
        gap: 20px;
        padding: 0 20px
    }
}
// story_card
.story-card {
    @w();
    position: relative;
    z-index: 999;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-top: 100px;
    & .top {
        display: grid;
        grid-template-columns: 42px auto;
        gap: 20px; 
        & .name {
            font-weight: 500;
            font-size: 20px;
        } 
    }
    & .middle {
        height: 240px;
        background: #a5ceff;
        border-radius: 20px;
        margin: 20px 0;
        text-align: center;
        & img {
            max-height: 240px;
        }
    }
    & .desc {
        font-size: 13px;
        line-height: 130%;
        color: #000000b3;
    }
    & button {
        background: linear-gradient(rgba(24, 32, 79, 0.4) 0%, rgba(24, 32, 79, 0.4) 100%);
        box-shadow: rgba(0, 0, 0, 0.15) 0px 20px 40px, rgba(0, 0, 0, 0.2) 0px 0px 0px 0.5px inset;
        border-radius: 30px;
        text-transform: uppercase;
        border: 0;
        margin-top: 20px;
        font-size: 13px;
        color: #fff;
        padding: 8px 15px;
    }
}
.story-l {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
.story-l-left .top {
    & .info {
        font-style: 13px;
    }
    & img {
        border-radius: 50%;
    }
}
.story-r-top,
.story-r-bottom {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    align-content: start;
}
.story-r {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    & .pic {
    height: 240px;
    background: #000000;
    border-radius: 20px;
    overflow: hidden;
    }
    & img {
        max-height: 240px;
    }
    & .toggle {
        display: none;
    }
}
.story-l>div,
.story-r>div {
    border-radius: 20px;
    box-shadow: #0000001a 0px 0px 0px 0.5px inset;
    background-color: #ffffff80;
    backdrop-filter: blur(10px);
    padding: 20px;
}
@media screen {
    @media (max-width: 1250px) {
        .story-card {
            grid-template-columns: 1fr;
            max-width: 768px;
        }
    }
    @media (max-width: 680px) {
        .story-l {
            grid-template-columns: 1fr;
            max-width: 400px;
            margin: 0 auto;
        }
        .story-r .toggle {
            display: grid;
        }
        .story-r .info .top {
            display: none;
        }
        .story-r-top,
        .story-r-bottom {
            grid-template-columns: 1fr;
            max-width: 400px;
            margin: 0 auto;
        }
    }
}
// bottomBox
.footer {
    position: relative;
    width: 100%;
    height: 800px;
    background: rgb(30, 19, 87);
    margin-top: 100px;
    // 利用svg裁剪盒子
    // clip-path: url(#wave2);
    & .con {
        overflow: hidden;
        position: absolute;
        top: -300px;
        left: 0;
        width: 100%;
        // background-color: pink;
    }
    & svg {
        width: 100%;
    }
}
.bolang {
    position: absolute;
    left: 0;
    top: 150px;
    width: 100%;
    height: 600px;
    background: linear-gradient(#130c3ecc 0%, #1e1357 28%);
    /* 使用svg裁剪盒子 */
    clip-path: url(#wave2);
}
/* 如果超过1400像素，波浪放大 1.5倍 */
@media (min-width: 1400px) {
    .bolang {
        transform: scale(1.5);
    }
}
.footer-con {
    position: absolute;
    top: 200px;
    left: 50%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    transform: translate(-50%, -50%);
    width: 660px;
    padding: 0 20px;
}
@media (max-width: 600px) {
    .footer-con {
        grid-template-columns: 1fr;
        justify-items: center;
        max-width: 400px;
    }
}
.footer-con-left {
    display: grid;
    grid-template-columns: 144px 144px;
    gap: 20px;
    & .item {
        display: grid;
        grid-template-rows: repeat(5, 44px);
        row-gap: 20px;
        & button {
            display: flex;
            width: 144px;
            height: 44px;
            /* justify-content: center; */
            align-items: center;
            border-radius: 10px;
            background: none;
            border: 0;
            outline: 0;
            cursor: pointer;
            padding-left: 10px;
            transition: all 0.3s ease-in-out;
            &:hover {
                background: #ffffff33;
                box-shadow: #1f2f4740 0px 20px 40px, #0000001a 0px 1px 5px, #ffffff66 0px 0px 0px 0.5px inset;
            }
            & img {
                width: 24px;
                height: 24px;
                margin-right: 10px;

            }
        }
        & a {
            text-decoration: none;
            color: #fff;
            & p {
                color: #fff;
            }
        }
    }
}
.footer-con-right {
    color: rgba(255, 255, 255, 0.7);
    font-size: 13px;
    padding-top: 60px;
    & p:nth-child(2) {
        margin-top: 20px;
    }
    & p:nth-child(3) {
        margin: 20px 0;
        font-weight: 500;
    }
}